I have a 2007 Montero Sport automatic. I had a strange accident. I parked my car on a nearly level slope while I ran into a convenience store. Apparently I forgot to both shift it out of gear and to set the e-brake, but turned the motoer off and locked the door. While inside, I see the car drifting down the road. I run out, funble for my keys, and realize I won't safely have time to get in and hit the brakes before it rolls off the edge of the road. So I had to watch it go. It roiled over a big rock, flipped on its left side, and crashed into a flat slope about 25' down an inclined slope.

The front body panels are all smashed, but the radiator was fine. We righted it and towed it to a shop. But for an inexplicalbe reason, the crankshaft won't turn. Put a wrench on it, and it only moves about 1/4 rotation before it stops. We checked the one easily reachable sparkplug for oil that may have seeped in while on its side,
but it was clean. What could cause this to happen?